/// @dir toneGen
/// Tone generator based on a discrete DAC.
// 2010-11-18 <jc@wippler.nl> http://opensource.org/licenses/mit-license.php

#include <JeeLib.h>
#include <avr/pgmspace.h>

byte index;

byte sine256[] PROGMEM = { 
    127,130,133,136,139,143,146,149,152,155,158,161,164,167,170,173,176,178,181,
    184,187,190,192,195,198,200,203,205,208,210,212,215,217,219,221,223,225,227,
    229,231,233,234,236,238,239,240,242,243,244,245,247,248,249,249,250,251,252,
    252,253,253,253,254,254,254,254,254,254,254,253,253,253,252,252,251,250,249,
    249,248,247,245,244,243,242,240,239,238,236,234,233,231,229,227,225,223,221,
    219,217,215,212,210,208,205,203,200,198,195,192,190,187,184,181,178,176,173,
    170,167,164,161,158,155,152,149,146,143,139,136,133,130,127,124,121,118,115,
    111,108,105,102,99,96,93,90,87,84,81,78,76,73,70,67,64,62,59,56,54,51,49,46,
    44,42,39,37,35,33,31,29,27,25,23,21,20,18,16,15,14,12,11,10,9,7,6,5,5,4,3,2,
    2,1,1,1,0,0,0,0,0,0,0,1,1,1,2,2,3,4,5,5,6,7,9,10,11,12,14,15,16,18,20,21,23,
    25,27,29,31,33,35,37,39,42,44,46,49,51,54,56,59,62,64,67,70,73,76,78,81,84,
    87,90,93,96,99,102,105,108,111,115,118,121,124,
};

void setup () {
    // Serial.begin(57600);
    // Serial.println("\n[toneGen]");
    pinMode(14, OUTPUT);
    pinMode(15, OUTPUT);
    pinMode(16, OUTPUT);
    pinMode(17, OUTPUT);
    pinMode(4, OUTPUT);
    pinMode(5, OUTPUT);
    pinMode(6, OUTPUT);
    pinMode(7, OUTPUT);
    cli();
}

void loop () {
    for (;;) {
        byte b = pgm_read_byte(sine256 + index++);
        PORTD = (PORTD & 0x0F) | (b & 0xF0);
        PORTC = (PORTC & 0xF0) | (b & 0x0F);
        // delayMicroseconds(2);
    }
}
